Abstract:
Sweetcom seeds, which usually deteriorate quickly duringstorage, are important for sweet corn production.
Many techniques and methods have been studied to preserve the amount of high quality seeds. In this work,
two lines of sweet corn seeds are kept in aluminium foil bags within an atmosphere of 100%N2, 100%CO2, a
mixture of 60% CO2 / 40% N2 as well as ambient air (control sample) at 10,30 and 40 ํC for 8 months. The
initial fungal contamination, lipid content, lipase and catalase activities of 'WTS 111' seeds are higher
compared to 'CPS 222', which exhibits a higher moisture and protein content. Germination, germination after
accelerated ageingand free fatty acid content show no significant difference between both lines. Germination
of 'WTS 111' declines lower than the standard valueof Thai Seed Act (75%for maize seed) after storage for
4 months at 40 ํC whereas 'CPS 222' is degraded within 2 months. However, after8 months storage of seeds
at lower temperature (10 and 30 ํC),the germination of 'WTS 111' and 'CPS 222' seeds reaches 86-87% and
80-82%, respectively. Germination after accelerated ageingfor both lines markedly declines correlated with
their fungal contamination which is highest for the seeds stored at 40 ํC after 1 month. In addition, protein,
lipid and free fatty acids contents as well as their lipase and catalase activities change lessat 10 ํC compared to
storage at 30 and 40 ํC. The germination of 'WTS 111' seeds is not affected by the composition of the gas
atmosphere in a package but 60%CO2 /40% N2 mixture delays fungal contamination and protein content in
'WTS 111'. However, the germination and fungal contamination of the 'CPS 222' seeds kept in 100% CO2 or
60%CO2 /40% N2 mixture is more delayed compared to storage in 100%N2 or ambient air.For both lines of
seeds, the composition of the atmosphere during storage does not affect the lipid content nor the germination
after accelerated ageing. The increase of free fatty acid content in 'CPS 222' seeds shows no influence due to
the gas composition during storage, but 'WTS 111' seeds kept in 100% CO2 exhibits the lowest free fatty acid
content. The moisture contentis not affected by the temperature nor the composition of the atmosphere used
during storage.
Hence, germination of sweet corn seeds for both lines kept in aluminium foil bags below30 ํC for 8 months is
greater than 80%,correlated with retardation of fungal contamination and physiological changes. The 'CPS
222' seeds stored in a package flushed with 100% CO2 or 60% CO2 / 40% N2 mixture exhibits higher
germination than that with 100% N2 and ambient air but 'WTS 111' reveals no difference among the
composition of the atmosphere.